Possible effects of HIV infection on overall survival of patients diagnosed with acute myeloid leukaemia

Abstract

Background

The effects of Human Immunodeficiency Virus (HIV) on the Overall Survival (OS) in patients diagnosed with Acute Myeloid Leukaemia (AML) are not well documented. All studies to date have been with small sample sizes and based on collections of case studies from different facilities with different treatment protocols, as a result it has been difficult to draw definitive conclusions.

Method

This retrospective record review of a cohort of AML patients (n=304) treated at a single site between 2000 and 2017 was conducted. Age (16-93 years), gender (Male: n=157 ; Female: n=138), ECOG PS (Eastern Co-Operative Oncology Group Performance Status), FAB (French-American-British) staging, blast count, CD4 count, HIV viral load, financial status, response to treatment as measured on bone marrow biopsy and OS were measured. The OS was compared for HIV status. Further comparisons were conducted in a sub-group where age, ECOG PS and FAB staging were controlled.

Results

210 (69.07%) were HIV negative, 31 (10.1%) were HIV positive, 63 (20.7%) had an unknown HIV status. A statistically significant difference was found between HIV negative and HIV positive groups’ OS (563 vs. 121 days ; P<0.01)(HR 2.02 ; 95% CI 1.36 - 2.99) in the main analysis. This difference was also noted when patients who were not treated for AML were excluded from the comparison (OS, 740 vs 194 days, P<0.01)(HR, 2.10 ; 95% CI 1.26-3.50). In the main analysis mean ECOG PS was better in the HIV negative population compared to the positive population (1.80 vs. 2.06). In the controlled group sub-study, where Age, ECOG PS and FAB staging were controlled, the OS between HIV positive and HIV negative patients was not statistically significant (141 days vs. 121 days) (P=0.17; 95% CI). CD4 counts ranged from 29 – 1416, with a mean CD4 of 432 on presentation. No statistically significant difference could be found between CD4 and OS (HR, 1.0 ; 95% CI 0.99-1.00), possibly due to very few patients presenting with a low CD4 count. HIV Viral Loads ranged from <100 – 106640. Similarly, no statistically significant difference was found between HIV Viral Load and OS (HR 0.99 ; 95% CI 0.99-1.00).

Conclusion

HIV has a negative impact upon the OS of patients with AML. HIV appears to impact on OS as a chronic comorbidity by affecting ECOG PS on presentation, reducing their chance of being treated as well as possibly reducing a patients’ functional reserve. This impact does not appear to be as a result of a direct interaction between the HIV and AML disease processes, as when controlling for other factors that may influence OS there is no statistically significant difference in OS between HIV positive and negative patients.